Fluoroolefins represented by formula: CF3(CX2)nCF═CH2, formula: CF3(CX2)nCH═CHF, or the like, are compounds having a useful structure as various functional materials, solvents, refrigerants, blowing agents, and the monomers for functional polymers or starting materials of such monomers. For example, fluoroolefins are used as monomers for modifying an ethylene-tetrafluoroethylene copolymer. Further, of the fluoroolefins mentioned above, the compound represented by CF3CF═CH2 (HFO-1234yf) and the compound represented by CF3CH═CHF (HFO-1234ze) have recently gained attention, as they offer promising prospects as refrigerants of low global warming potential.
As processes for producing the fluoroolefins represented by the formulae above, many processes have been reported in which a starting material chlorine-containing alkane or chlorine-containing alkene having the same number of carbon atoms as that of a target fluoroolefin is reacted with a fluorinating agent such as an anhydrous hydrogen fluoride in the presence of a catalyst. In these processes, chromium oxide catalysts, antimony catalysts, etc., are used as catalysts. In particular, chromium oxide catalysts are widely used because of ease of industrial use (e.g., Patent Literature 1).
However, the conversion of a starting material is not particularly high when a chromium oxide catalyst is used; in this case, a huge reaction facility is necessary to obtain a sufficient production amount per unit time, and it is uneconomical in view of facility cost and operation cost.
Moreover, when a chromium oxide catalyst is used, several byproducts, which sometimes cannot be converted to target products, are generated, causing problems such as a reduction in the yield of target fluoroolefin, complications in a purification step, rise in the costs of the facility used in the purification step, and the like. Further, when a chromium oxide catalyst is used, since the activity is significantly deteriorated depending on the conditions, use of an activity deterioration inhibitor, which is not necessary in conventional reactions, is needed, which becomes one of the causes of the rise in costs due to an increase of byproducts and a complicated production step.